Etymology of the English word breastbone
the English word breastbone
derived from the English word breast
derived from the English word bone
derived from the English word fish
derived from the English word fisc
derived from the Proto-Germanic root *fiskaz
derived from the English word head
derived from the Proto-Germanic root *khaubuthan
derived from the Proto-Indo-European root *kaput- (head)
derived from the English word yard
derived from the Proto-Germanic root *bainam
derived from the New Latin word breastbone